diff --git a/src/main/ui/static/config/bdprize/bdprize.js b/src/main/ui/static/config/bdprize/bdprize.js
index fdd6f20f6..b3ad7aded 100644
--- a/src/main/ui/static/config/bdprize/bdprize.js
+++ b/src/main/ui/static/config/bdprize/bdprize.js
@@ -251,7 +251,7 @@ define(['angular', '../../analysis/bd/analysis-bd'], function (angular) {
         $scope.chooseLastConfig = function (mon) {
             let year = new Date(mon).getFullYear();
             let month = new Date(mon).getMonth();
-            if(index == 0){
+            if(month == 0){
                 year--;
                 month = year + '-12';
             }else if(month <= 9){